This 1975 school bus did not meet federal air quality or motor vehicle safety equipment standards. It was destroyed and replaced with a newer, cleaner and safer vehicle.

Photo courtesy of the San Diego County Air Pollution Control District

This 2008 model year school bus replaced Dehesa School District’s 1975 school bus. The new bus emits about 95 percent less particulate matter (PM) and approximately 85 percent less nitrogen oxide (NOx) than the bus it replaced.

Photo courtesy of the San Diego County Air Pollution Control District

This is one of 83 San Diego County school buses retrofitted with an active diesel particulate filter (DPF). Active DPFs are cleaned or regenerated using an integrated heating element which burns off the diesel particulate matter (PM).

Photo courtesy of the San Diego County Air Pollution Control District

This label and indicator lights on the operator panel let the driver know when diesel particulate filter needs to be cleaned or regenerated.

Photo courtesy of the San Diego County Air Pollution Control District

The Cajon Valley Union School District bus fleet is ready to roll after participating in San Diego Air Pollution Control District’s initiative to replace, repower, or retrofit 125 high-polluting buses.